[PATCH AUTOSEL 4.14 58/59] qmi_wwan: Fix qmap header retrieval in qmimux_rx_fixup

Sasha Levin
2018-12-26T22:41:53Z

From: Daniele Palmas <dnlplm@gmail.com>

[ Upstream commit d667044f49513d55fcfefe4fa8f8d96091782901 ]

This patch fixes qmap header retrieval when modem is configured for
dl data aggregation.

Signed-off-by: Daniele Palmas <dnlplm@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/usb/qmi_wwan.c | 15 ++++++++-------
1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/drivers/net/usb/qmi_wwan.c b/drivers/net/usb/qmi_wwan.c
index d88e6a15022b..429d08a68a63 100644
--- a/drivers/net/usb/qmi_wwan.c
+++ b/drivers/net/usb/qmi_wwan.c
@@ -151,17 +151,18 @@ static bool qmimux_has_slaves(struct usbnet *dev)

static int qmimux_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
{
- unsigned int len, offset = sizeof(struct qmimux_hdr);
+ unsigned int len, offset = 0;
struct qmimux_hdr *hdr;
struct net_device *net;
struct sk_buff *skbn;
+ u8 qmimux_hdr_sz = sizeof(*hdr);

- while (offset < skb->len) {
- hdr = (struct qmimux_hdr *)skb->data;
+ while (offset + qmimux_hdr_sz < skb->len) {
+ hdr = (struct qmimux_hdr *)(skb->data + offset);
len = be16_to_cpu(hdr->pkt_len);

/* drop the packet, bogus length */
- if (offset + len > skb->len)
+ if (offset + len + qmimux_hdr_sz > skb->len)
return 0;

/* control packet, we do not know what to do */
@@ -176,7 +177,7 @@ static int qmimux_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
return 0;
skbn->dev = net;

- switch (skb->data[offset] & 0xf0) {
+ switch (skb->data[offset + qmimux_hdr_sz] & 0xf0) {
case 0x40:
skbn->protocol = htons(ETH_P_IP);
break;
@@ -188,12 +189,12 @@ static int qmimux_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
goto skip;
}

- skb_put_data(skbn, skb->data + offset, len);
+ skb_put_data(skbn, skb->data + offset + qmimux_hdr_sz, len);
if (netif_rx(skbn) != NET_RX_SUCCESS)
return 0;

skip:
- offset += len + sizeof(struct qmimux_hdr);
+ offset += len + qmimux_hdr_sz;
}
return 1;
}
--
2.19.1